1. Field of the Invention
The present invention relates to an image processing apparatus for processing such as image formation on the basis of a digital signal obtained by converting, e.g., an optical image into an electrical signal.
2. Related Background Art
In order to obtain a color image hard in a conventional color printer of a thermal transfer system or an electrophotographic system, color developing agents of Y (yellow), M (magenta), C (Cyan), and BK (black) are sequentially mixed according to mixing of subtractive primaries, thereby obtaining a full-color (all colors) image hard copy. In this case, the Y, M, C and BK image must be precisely aligned on a single recording medium (a recording sheet).
For this reason, when color image information read by a color image reading apparatus (i.e., a color reader) is to be sequentially printed or an image processing apparatus does not include an image memory, synchronization control for performing color image registration between the color reader and the color printer is required.
In order to obtain a plurality of color image hard copies or identical color image hard copies at different places, the color image information read by a single color reader must be supplied to a plurality of color printers.
However, if a single color reader is connected to a plurality of color printer, the following problem occurs.
After an image formation command is simultaneously input to a plurality of printers, an initial preparatory operation such as preliminary rotation must be performed at each printer for subsequent image formation. In this case, the preparatory periods required for the initial preparatory operation at different printer are often different from each other, and the recording start timings are also different from each other. If the image signal is supplied from a single reader to a plurality of printers at the same timing, supply of the image signal cannot be synchronized with the start of image recording at some printers. In order to eliminate this problem, differences in recording start timings may be absorbed by a large-capacity memory means such as a page memory. However, this arrangement undesirably results in high cost.